The invention relates to a head rest carrying element for connecting a head rest to a seat, more particularly to a motor vehicle seat.
From DE 297 17 568 U1 there is already known a frame for motor vehicle head rests which is produced from a formed tubular piece consisting of light metal.
EP 0 916 549 B1 proposes a head rest for motor vehicle seats, which head rest comprises padding in which there is received a frame. The head rest is held by a pair of bars, with the height of the frame of the head rest being adjustable relative to the bars. The bars are connected to the back rest of the motor vehicle seat.
From EP 1 481 743 A2, it is known to use flexibly rolled strip material whose thicknesses vary in the longitudinal direction of the strip to produce a sheet metal element and to form this into a tubular member with an out-of-round cross-section. By carrying out a forming operation in the longitudinal direction of the strip, it is possible to produce a tubular member whose wall thickness varies along its length or, by carrying out a forming operation transversely to the longitudinal direction of the strip, to produce a tubular member whose wall thickness varies around the circumference.
DE 102 10 156 A1 describes a process of producing a tube which comprises a plurality of tube portions whose wall thicknesses differ from one another. The process comprises the following process stages: forming a sheet metal piece with a non-uniform thickness profile into tubular member and welding this into a tube. A tube produced in this way can be used as a roll bar for a motor vehicle.
From DE 603 07 484 T2 there is known a tool which serves to stamp notches into the tube of a head rest.